A variety of liquid crystal polymer and copolymer compositions are known to persons in the art.
R. W. Lenz et al. in Polymer, 1991, Volume 32, Number 9, pp. 1703-1712, discuss the synthesis of extended rod thermotropic polyesters with polyoxyethylene pendant substituents. One class of thermotropic polyester composition which was shown by Lenz et al. and which was designated as "Series VI" contained alkoxy (e.g., methoxy or ethoxy) or --(OCH.sub.2 CH.sub.2).sub.n OR', with R' being methyl or ethyl, side chains on a para-phenylene group derived from an analogous hydroquinone reagent and also contained a terephthaloyl group. Such polyesters were indicated as lacking a flexible alkylene spacer unit which was included in earlier polymers designated as "Series IV" which also comprise a linkage: Ar--C(O)OArOC(O)--Ar--having alkoxy or (OCH.sub.2 CH.sub.2).sub.n OR' substitution on the central phenylene ring. This reference does not speak of incorporation of such thermotropic polyesters for fiber production.
British Patent No. 2,161,171 gives another example of wholly aromatic polyesters having liquid crystalline characteristics which can include terephthaloyl, isophthaloyl, and alkoxy-substituted para-phenylene groups as essential components. It mentions production of fibers, films and molded articles at page 1, line 8, but appears to contemplate melt processing of the liquid crystalline polymer alone (see page 4, line 65, page 5, lines 32-39 and page 7, line 59, for example).
Isayev et al. in U.S. Pat. No. 4,728,698 speaks of incorporation of various thermotropic liquid crystal polymers into a variety of base polymers including polyesters. Wholly aromatic polyester thermotropic liquid crystal polymers are preferred.